Step 1

Finely grate 3 ounces Pecorino Romano cheese (about 1 1/2 packed cups). Coarsely grind enough black pepper to get 2 teaspoons.

Step 2

Heat 2 tablespoons olive oil in a medium (3.5-quart or larger) Dutch oven or pot over medium heat until shimmering. Add the black pepper and 1 pound dried orzo, and sauté until the orzo is toasted in spots and the mixture is fragrant, 1 to 2 minutes.

Step 3

Add 3 cups water, 2 cups whole or 2% milk, and 1 1/2 teaspoons kosher salt, and bring to a boil. Reduce the heat to medium-low to maintain a simmer. Cook uncovered, stirring frequently to keep the orzo from sticking, until the orzo is al dente and most of the liquid is absorbed and has formed a creamy sauce, 10 to 12 minutes.

Step 4

Remove the pot from the heat. Add 1 packed cup of the Pecorino and stir until melted, about 30 seconds. If serving as a main dish, transfer to individual bowls and dollop with a generous spoonful of ricotta cheese, if using. If serving as a side dish, serve it right out of the pot or transfer to a large serving bowl. Garnish with the remaining Pecorino, several grinds of black pepper, and a generous drizzle of olive oil.